Apparatus for severing string ends



Jan. 3, 1956 B. c. MCCREARY ETAL 2,729,484

APPARATUS FOR SEVERING STRING ENDS Filed Sept. 29. 1952 4 Sheets-Sheet 1 In imIfmnilhIIlr:-

2 INVENTORs, 58x75 67 4695 04/145? W400 ATTORNEY TJE1.EJ

Jan. 3, 1956 B. c. MCCREARY ETAL 2, 84

APPARATUS FOR SEVERING STRING ENDS Filed Sept. 29, 1952 4 Sheets-Sheet 2 Tac lL.

QLMJZ ATTORNEY Jan. 3, 1956' Filed Sept. 29, 1952 B. c. MOCPEARY ETAL 2,729,484

APPARATUS FOR SEVERING STRING ENDS 4 Sheets-Sheet 3 INVENTORS. 52005 C. Afirfemer 04/1 54 1% 4 000 BY flmaedgy/ ATTORN EY Filed Sept. 29, 1952 B. C. M CREARY ET AL APPARATUS FOR SEVERING STRING ENDS 4 Sheets-Sheet 4 IN V EN TORS.

United States Patent- APPARATUS FOR SEVERING STRING ENDS Bruce C. McCreary, Bound Brook, and Oliver W. Wood,

Rahway, N. J., assignors to Johnson & Johnson, a corporation of New Jersey Application September 29, 1952, Serial No. 312,132

' 16 Claims. 01. 289-1) This invention relates to apparatus for cutting off loose string ends adjacent the knot of a string tied about a package. Although not limited thereto, it is particularly applicable for cutting off up close to the knot the ends of a string that has been tied around the neck of a bag.

In accordance with the preferred embodiment of the invention, a string clamping device mounted on a horizontal turret is rotated to a position to receive one end of a string that has been tied, about the neck of a bag and knotted. The knot tying machine for which the herein described embodiment of the invention may serve as an attachment, may be such that once such end of the string has been clamped by the string severing device, the tied article is discharged from the machine, while the other end of the string remains held by the machine to apply tension to both ends of the string at opposite sides of the knot to tighten it.

When the knot has been tightened, a pair of clamping devices carried one on each of a pair of twin turrets rotating on angularly disposed intersecting axes grips the string at opposite sides of the knot at positions where the peripheries of the turrets have their widest separation. Thereupon, the end of the string which still is attached to the knot tying machine is severed beyond the position of the adjacent clamp. As the twin turrets continue their rotation, the free ends of the string are moved toward each other and into a slot presented by inclined plate members, while the package passes therebeneath. Further rotation of the turrets draws the package up close to the underside of the plate members, tensions the string ends and moves them into engagement with a rotatable cutting knife located just above the inclined plate members with the result that the string ends are cut off close 1 to the package. The released package drops down into an underlying chute while the severedstring ends are released by the clamps and disposed of;

A better understanding of this invention may behad by reference to the following drawings in which:

Fig. l is a plan view of a string cut-off device equipped with the present improvements; j v

Fig. -2 is a horizontal section on line 2-2 of Fig. 3;

Fig. 3 is a vertical section on line 3-3 of Fig. 1;

Fig. 4 is a vertical section on line 44 of Fig. 1;

Fig. 5 is a face view of one of the twin clamp carrying turrets, looking at the parts in the direction of the arrow 5 in Fig. 1; v I

Fig. 6 is a vertical section on line 6+6 of Fig. 1;

Fig. 7 is an elevation of the parts looking in the directionof the arrow 7 in Fig. l; I

. Figs. 8 and 9 are views similar to Figs. 6 and 7 respectively, but showing the parts in a difierent portion of the machine cycle; and

Figs. 10 and 11 likewise are views similar to Figs. 6 and 7 respectively, but showing the parts at still a different position of the machine cycle.

A package exemplified by a surgicalsponge S in the form of cotton encased in a gauze bagjwhose ends are tied by a closing string may be made on a machine hav-' plurality of clamps 11 disposed near the peripheral edge of a horizontal rotatable turret 12 fixed at the upper end of a vertical shaft 13 journaled in bearings 14 secured to a fixed frame member 15 of the machine (see also Fig- 3). In the embodiment illustrated, the turret 12 is equipped with four such clamps 11 spaced at 90 intervals aboutvits periphery to handle different sponges in order as they are completed on the machine.

The horizontal turret comprises top and bottom plates 16 and 17 of one diameter and a central or intermediate plate 18 of somewhat larger diameter and all secured together for operation as a unit.

At each clamp location, the central disc 18 is formed with a radially disposed rectangular slot 19 of given width, whose inner end 20 terminates near the center of the disc and whose outer end 21 terminates near the periphery of the disc except for a section 22 of narrower. width which extends through to the periphery. A finger or slide 23 of thickness equal to that of the central disc is guided by the lateral edges of the slot 19 for radial movement inwardly and outwardly of the slot. The finger 23 has a narrow portion 24 near its outer end which fits into the narrower outer end section 22 of the slot and at its extreme outer end it is provided with a lateral extension 25 constituting a jaw which, with the adjacent peripheral edge of the disc 18 constitutes a pair of jaws in which a string can be retained.

' The narrow portion 24 of the finger 23 is somewhat longer in a radial direction than is the length of the narrow section 22 of the slot in which it is guided so that movement of the finger in a radial direction is limited in an outward direction by the engagement of a shoulder 26 presented by the slide at the inner end of its narrow portion 22 with the adjacent end portion 21 ofthe slot, and in an inward direction by engagement of the jaw 25 and the disc 18 with each other or with a string clamped therebetween.

The finger 23 is formed with a rectangular aperture 27 to accommodate a compression spring 28 which reacts between the inner end of such aperture and, a pair of abutments 29, 30 presented at the front end of opposed recesses 31,32 formed in the inner faces of the two outer turret plates 16, 1,7 in radial alignment with the rectangular aperture 27 in the fingen' The recess in the lower plate is cut all the way through the plate as at 33 to provide clearance for in and out radial movement therein and inwardly to close upon the string when the cam follower meets a low portion of the cam.

A chain 37 which may be driven from the sponge forming turret 10 may be used to drive the horizontal clamping turret 12 in synchronism therewith and at a speed such that when one or another of the clamps 11 arrives at position x, a completed sponge S arrives simultaneously at the same position. The drive also is such that when a clamp 11 and a sponge S arrives at such position, the sponge is traveling at a somewhat higher Patented Jan. 3, 1956 speed than the clamp so that the free end of its string is inserted between the periphery of the disc 18 and the jaw 25, constituting the clamp 11, which, it will be noted has its opening facing rearwardly as regards the direction of rotation of the turret 12 (Fig. 1). The clamp 11 is opened to receive the string end as it is rotated to position x by engagement of the cam follower 35 associated with such clamp with a high portion 38 of the fixed cam 36 which is appropriately located for this purpose. As soon as the string end s has been located between the jaws of the clamp, the cam follower 35 drops off the high portion of the cam 36 on to a low portion thereof, permitting the spring 28 to move the finger 23 inwardly to close the clamp upon the string.

After the clamp 11 closes upon the string, the knot which has been tied therein and which holds the sponge cover in place, is pulled up tight as the turret clamp 11 holding the end s of the string and the sponge forming turret station from which the sponge has been removed and to which the other unsevered end s is still connected, rotate away from their common position x first to position y and then to position z. In order that the tension exerted to secure tightness in the knot does not pull the string out of the turret clamp 11, additional pressure is exerted on the finger 23 to press the jaw 25 tightly against the string. To this end, the cam follower 35 upon leaving position x drops off the high portion 38 of the external cam 36 and engages a floating internal cam 39 which presses against it (Figs. 2 and 3). The cam 39 is presented by the vertical internal face of a shoe 40 arranged for limited sliding movement radially of the turret 12 as determined by a pair of headed studs 41 passing vertically through a pair of parallel slots 42 in the shoe, and threaded into an underlying platform 43 supporting the shoe and fixed to the underface of the fixed external cam 36. The shoe 40 is pressed against the cam follower by a pair of relatively strong compression springs 4 seated in a pair of parallel recesses 45 drilled into the outer vertical face of the shoe horizontally inwardly toward the center of the turret and whose outer ends react against a vertical abutment 46 fixed to the top side of the platform 43 which supports the movable shoe. The arrangement is such that as the string with sponge attached moves from the dot and dash position y shown in Fig. 2 to the solid line position zshown therein, the jaw 25 is pressed tightly to hold the string by the engagement of the cam follower 35 with the internal cam 39 and during this period the knot is pulled up just about as tight as is feasible.

When the knot has been tightened thus, the string ends s, s at the opposite sides of the sponge S are grasped by one of a plurality of pairs of clamping devices 47 and 48 presented by carrier means such as a pair of smaller twin turrets 49 and 50 which carry the string first to a severing device 51 which cuts the cordin thatportion s" thereof that still is attached to the sponge forming turret and then transfers the sponge with the relatively long string ends s, s still attached thereto to a position where such ends are cut ofi": up close to the knot-(Figs. l, 4 and The twin turrets 49 and 50 except for being smaller than the horizontal turret 12 previously described-have for the most part a similar construction (Figs. 1, 4 andS). They consist each of three parallelcircular-discs 52, 53, 54 fastened together in facewise contact to operate as aunit, the outer discs 52 and 53 being of the same size and the intermediate disc 54 of somewhat large size. The intermediate disc is radially slotted to accommodate four clamping fingers 55 spaced thereabout at 90 intervals and which have rectangular apertures 56 to receive compression springs 57 which react between the inner ends of the apertures and shoulders presented by the outer ends of recesses 58 and 59 sunk into the opposed inner faces of the outer discs 52, 53 in substantial alignment with the apertures in the fingers. The turrets are-disposed for rotation in vertical intersecting planes and to.

this end are fixed at the inner opposed ends of horizontal shafts 60 and 61 whose axes, if extended would intersect. The shafts 60, 61 are journaled in gear boxes 62, 63, supported on a fixed part 15 of the machine and from which there downwardly extend vertical shaft 65, 66 driven by a chain 67 from the larger horizontal or main turret 12. The twin turrets are arranged to rotate at the same angular speed as the larger turret.

The fingers 55 in the small twin turrets are the same in number as in the larger turret. They are equipped each at their outer end with a jaw element 63 arranged for cooperation with the outer peripheral edge of the intermediate plate 54 to provide the string clamping devices 47, 48. The fingers 55 are arranged for radial movement toward and away from the center of the respective turrets under the influence of an external cam 69 fixed one on each of the associated gear boxes 62, 63 in a position encircling the turret drive shafts 60, 61. A cam follower 70 disposed on the end of a stud 71 fixed in and which projects laterally from each of the fingers 55 through an aperture formed in the inner turret plates tracks along the cam to impart desired radial movement to its associated finger.

Corresponding clamps 47 and 48 on the respective turrets operate in pairs. When each pair of clamps, during the rotation of the turrets which is in a clockwise direc tion looking in the direction of the arrow 5 in Fig. 1, approaches the position of their widest separation which is approximately at the level of the larger horizontal turret 12, the clamps are opened by engagement of their cam followers 70 with a high portion of their associated earns '69 to grasp the string ends s, s at opposite sides of the sponge, which ends have been drawn up taut as previously described and as indicated at position 1 in Fig. 1 and in Figs. 6 and 7. The clamps, as soon as they engage the taut string ends s, s are closed to clamping position under the action of their springs 59, as their cam followers 70 ride off the high portions of their associated cams. As the twin turrets continue their rotation, the clamped string ends move downwardly to bring that portion of the string .9" which is between the knot tying machine and the nearest turret into engagement with the severing device 51 which consists of a rotating disc knife 72, vertically disposed on a horizontal shaft 73 arranged in a sleeve bearing 74 supported by the fixed part of the machine 15 and whose end opposite the knife is belt connected with a driving motor 75 likewise mounted on the same machine part (Fig. 1). When the string is severed, the clamps 47, 48 on the twin turrets hold the free ends s, s of the strings from which thesponge 'S dangles downwardly under the force of gravity (Figs. -6 and 7). It should be understood that when the string'ends previously held by theclamp 11 onthe larger turret 12 is transferred to the clamp 47 on the smaller turret, it is released by the former clamp, as the pressure exerted on the string by such clamp is relieved due to the cam follower 35 associated therewith departing from the influence of the internal cam 39.

As the twin turrets 49, 50 continue their rotation, the string ends held by'the respective clamps 47, 48 thereon move closer together permitting the sponge to hang down freely between them as shown in Figs. 8 and 9. As the clamps during the rotation of the turrets pass through their 'lowes't points and start moving upwardly, the string ends s, s pass into an opennig 76 between a pair of inclined plates 77, 78 supported on the fixed part 15 of the machine. The opening 76 between the inclined plates-is flared downwardly to insure entry of the strings therebetween and passage thereof up into a smaller narrower opening between the platesin thenature of a slot 79. As the string ends enter the slot 79, the sponge passes beneath the inclined plates.

Further rotation of the twin turrets 49, 50 carries the string ends upwardly; causingthe sponge to engage the underside of the inclined plates 77,178 thereby tensioning the string ends andcausing the sponge to slide upwardly and outwardly (Figs. and 11). This movement of the sponge brings the strings into engagement with a knife edge presented by a vertically disposed rotatable disc 80 fixed on a horizontal shaft 810i a driving motor 82 mounted on the fixed machine part 15. The edge of the disc 80 is beveled rearwardly substantially at the angle of the inclined plates 77, 78 so that the string ends are cut off at a point very close to the location of theknot. Severing of the string ends releases the sponge which drops through an aperture 83 in the fixed machine member 15 and into an underlying shute 84 which conveys the sponge away for further processing (Fig. 10). Also after the string severing operation has taken place and at a suitable location during rotation of the twin turrets, the clamps 47, 48 are operated by their springs 59 and as permitted by a low portion of their earns 69, to release the string ends which then are disposed of in convenient fashion. V

The operation of the machine will be clear, it is thought, from what has already been said. 1

The invention has been described in connection with one embodiment only, but many modifications thereof are within its spirit. The invention therefore should be limited only by the appended claims construed as broadly as the prior art permits.

What is claimed is:

1...An apparatus for cutting off excess string ends extending from the knot of a string tied on a package, the combination which includes movable carrier means equipped with clamping devices operable to grasp and hold the individual string ends extending from a knot on a package, means presenting a slot simultaneously to accommodate both string ends and for guiding the package in a given path of movement as tension is applied to the string ends after they have entered the slot, and a string severing device adjacent said means for cutting both string ends oil" close to the knot as the package is guided along said path, said carrier means being operable upon movement thereof to bring the string ends grasped in the clamping devices thereon into the guide slot and apply tension thereto.

' 2. In apparatus for severing excess, string ends extending from the knot of a string tied on a package, the combination which includes a plurality of turrets equipped each with a device for clamping and holding one of the individual string ends extending from a knot on a package, means presenting a slot simultaneously to accommodate both string ends and for guiding the package in a given path of movement as the string ends move along the slot and as tension is applied thereto, and mechanism arranged adjacent said means for cutting both string ends off close to the knot as the package is guided along said path, said turrets being rotatable to move the clamped strings into and along the slot and to apply tension thereto. 1 p

3. In apparatus for severing excess string ends extending from the knot of a string tied on a package, the combination which includes a plurality of turrets equipped each with a device for clamping and holding one of the individual string ends extending from a knot on a package, inclined plate means presenting a slot to accommodate the string ends and cutting mechanism arranged adjacent the top side of the plate means up close to the slot therein, said turrets being so located and arranged that upon rotation thereof the clamped strings are moved into and along the slot and the package guided along the underside of the plate means until the string ends are severed by the cutting mechanism.

4. In apparatus for severing excess string ends extending from the knot of a string tied on a package, the combination which includes a plurality of turrets mounted for rotation about angularly disposed intersecting axes and equipped each with a device for clamping and holding one of the individual string ends extending from a knot on a package, inclined plate means presenting a slot to accommodate the string ends cutting mechanism arranged adjacent the top side of the plate means up close to the slot therein but spaced from the entrance of the slot, and means for rotating the turrets to move the clamped string ends into and along the slot and the package along the underside of the plate means until the string ends are severed by the cutting mechanism.

5. In apparatus for severing excess string ends extending from the knot of a string tied on a package, the combination which includes a plurality of turrets mounted for rotation about angularly disposed intersecting axes and equipped each with a device for clamping and holding one of the individual string ends extending from a knot on a package, means acting during the rotation of the turrets to cause the clamp devices to grasp the string ends when said devices are at their points of widest separation, inclined plate means presenting a slot to accommodate the string ends and for guiding the package upwardly along the underside of the plate means as the string ends move along the slot and as tension is applied thereto, mechanism arranged adjacent the top side of the plate means for cutting the string ends of]? close to the knot as the package moves along the underside of the plate means, and means for rotating the turrets whereby the clamped string ends are moved closer together, into and along the slot, and tension is applied thereto.

6. A combination according to claim 1 in association with still another clamp for clamping the end of a string tied on a package, and means on which said last mentioned clamp is mounted for transporting said end of the string to one of the clamping devices forming part of said combination.

7. A combination according to claim 1 in association with still another clamp for clamping the end of a string tied on a package, and means on which said last mentioned clamp is mounted for transporting said end of the string to one of the clamping devices forming part of said combination, and means associated with said clamp and with the clamping devices forming part of said combination for operating them in synchronism.

8. In apparatus for tightening a knot in a string tied to a package and for cutting off excess string ends extending from the knot of said tied string, the combination which includes, a clamping device operable to grasp one portion of the string extending from the knot and movable as the other portion of the string extending from the knot remains held to apply tension to the string to tighten the knot, devices associated with said clamping devices and movable with respect to the string thus tensioned for grasping the tensioned string at opposite sides of the knot, means located in position for cutting loose the held portion of string during movement of said string grasping devices, and means cooperating with the movable string grasping devices and operable during the movement thereof for cutting off the string ends grasped by said movable devices up close to the knot.

9. In apparatus for tightening a knot in a string tied to a package and for cutting cit excess string ends extending from the knot, the combination which includes a clamping device operable to grasp one portion of the string extending from the knot and movable, as the other portion of the string extending from the knot remains held to apply tension to the string to tighten the knot, devices associated with said clamping devices and movable with respect to the string thus tensioned for grasping the tensioned string at opposite sides of the knot, a rotary device located in position to cut loose the held portion of the string during movement of said string grasping devices, means acting in conjunction with said string grasping devices and operable during the movement thereof individually to tension both said string ends, and a cutter co- '17 operating Wiflt ,said means for simultaneously :severing bothv saidiensionedv string ends up close to the' knot.

110. In apparatus, for tightening a knot in a. string tied tota package andfor cutting off excess string endsextendingfrom the knot, the combination which includes a clampingdevice operable to grasp one portion of the string extending from the knot and movable as the other portion of the string extending from the knot remains held to apply tension to the string to tighten the knot, movable devices for clamping the tensioned string at opposite sides of the knot, adevice for cutting loose the held portionvof the string during movement of said string clamping devices, means presenting a slot to accommodate said string ends and-to apply tension individually thereto as saidclamping devices continue their movement, and a cutter arrangedadjacent said slot and co-operating with the means that presents the slot for simultaneously severing both said-string ends up close to the knot.

11. In apparatus for tightening a knot in a string tied to a package and for cutting ofi excess string ends extending from the knot, the combination which includes a device presenting a clamp movable into a position to rec'eive one portion of the string extending from the knot and away-from ,saidposition while the other portion of the string remains held whereby tension is applied to the string to tighten the knot, means operable as the clamp moves toward said position first to open the clamp and then to close the clamp upon the string as the clamp moves away from said position, devices operable to grasp the tensioned string at opposite sides of the knot and movableto withdraw the initially free end portion of the string out of the first mentioned clamp device and to transport the other portion of the string past a cutting device to sever it from the portion that initially remained held, and mechanism for individually tensioning both string ends beyond the knot and for simultaneously severing them when thus tensioned as said string grasping devices continue their movement.

.12. In apparatus for tightening a knot in a string tied to a package and for cutting off excess string ends extending from the knot, the combination which includes a rotatable turret equipped with a clamp movable, as the turret rotates, into a position to receive one portion of the stringextending from the knot while the other portion ofthe string remains held whereby tension is applied to the ,string totighten the knot, means rendered operative ariasfiai bytlthek-rotationdf the.turretland as the clamp moves toward"said,position=toiopenthe clamp and-then to close theklamphponthe string as the clamp moves away'from said, position, a plurality of rotatable turrets equipped each with a clampmovable, as said turrets rotate to grasp the tensioned string at opposite sides of the knot and to withdraw the initial portion of the string out of the clamp device on'the'first mentionedturret and to transport the other portion of the string past a cutting device to sever itfrom the portion thereof that was initially held, an inclined'platform presenting a slot, and a cutting edge located adjacent'one side of theplatform in close proximity to"the'slot,'said' plurality of turrets being located withrespecttothe'platform and the cutting edge in such position'thatastheir rotation continues, the string ends held 'by'theclampsthereon'move into the slot, are tensioned by'the engagement of'the package with the side of the platform opposite the cutting edge, and are severed by the-cutting edge upclose'to the knot.

13. A combination-according to claim 12 wherein the plurality of rotatable'turrets are disposed on axes which intersecg'and whereinthe'string'ends are grasped by the clamps thereon near the'point of widest separation of the turrets and are brought to severing position near their point or closest proximity.

1 4 A combination according to claim 12 wherein the clamps on the respective turrets are cam operated against spring tension.

15. A combination according to claim 12 wherein the twin turrets areirotatable inplanes at right angles to the plane of rotation of the turret whose clamp initially grasps the-end of the string.

16. A combination according to claim 12 wherein the twin turrets-and the turret whose clamp initially grasps the end ofthe-string'areconnected together for rotation in-synchronism.

References Cited in the file of this patent UNITED STATES PATENTS 899,764 Rogers Sept. 29, 1908 2,197,397 Matousek Apr. 16, 1940 2,258,644 Demarest et al. Oct. 14, 1941 2,462,957 Gunn Mar. 1, 1949 2,613,399 Riordan et al. Oct. 14, 1952 2,639,069 West May 19, 1953 

